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<head><meta charset="utf-8"><title>meeting 2020-09-15 · wg-traits · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/index.html">wg-traits</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html">meeting 2020-09-15</a></h3>

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<a name="210182009"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182009" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182009">(Sep 15 2020 at 19:58)</a>:</h4>
<p>Hi <span class="user-group-mention" data-user-group-id="692">@WG-traits</span><br>
Meeting in 2ish minutes</p>



<a name="210182187"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182187" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182187">(Sep 15 2020 at 20:00)</a>:</h4>
<p>Howdy :)</p>



<a name="210182200"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182200" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182200">(Sep 15 2020 at 20:00)</a>:</h4>
<p>Today we're continuing sprint planning right?</p>



<a name="210182215"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182215" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182215">(Sep 15 2020 at 20:00)</a>:</h4>
<p>Meeting time :)</p>



<a name="210182249"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182249" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182249">(Sep 15 2020 at 20:00)</a>:</h4>
<p>hi hello hi howdy</p>



<a name="210182279"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182279" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182279">(Sep 15 2020 at 20:00)</a>:</h4>
<p>Before we start, anybody have an updates or announcements?</p>



<a name="210182390"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182390" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182390">(Sep 15 2020 at 20:01)</a>:</h4>
<p>Im working on chalk full time now, as promised :)</p>



<a name="210182414"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182414" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182414">(Sep 15 2020 at 20:01)</a>:</h4>
<p>That's awesome!</p>



<a name="210182495"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182495" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182495">(Sep 15 2020 at 20:02)</a>:</h4>
<p>We talked about opaque type/implied bounds interactions before, I'm not entirely sure what we meant with that but I wrote down <a href="https://github.com/rust-lang/chalk/issues/335#issuecomment-692298717">a comment</a> with some thoughts on that</p>



<a name="210182566"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182566" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182566">(Sep 15 2020 at 20:02)</a>:</h4>
<p>So, PR wise, we had 3 merged since last week: <code>Unpin</code>, (more) lowering improvements, and some debug printing update</p>



<a name="210182573"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182573" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182573">(Sep 15 2020 at 20:02)</a>:</h4>
<p>I was away for most of last week but I did spend a <em>bit</em> of time working on chalk yesterday, hoping to ramp that up next week :)</p>



<a name="210182595"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182595" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182595">(Sep 15 2020 at 20:02)</a>:</h4>
<p>Gosh I'm excited</p>



<a name="210182664"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182664" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182664">(Sep 15 2020 at 20:03)</a>:</h4>
<p>I think we said that we'd use this meeting to plan our first sprint</p>



<a name="210182698"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182698" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182698">(Sep 15 2020 at 20:03)</a>:</h4>
<p>Btw <span class="user-mention" data-user-id="251766">@Areredify</span> I left one small comment on your PR, but feel free to r+</p>



<a name="210182720"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182720" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182720">(Sep 15 2020 at 20:03)</a>:</h4>
<p><span class="user-mention silent" data-user-id="116009">nikomatsakis</span> <a href="#narrow/stream/144729-wg-traits/topic/meeting.202020-09-15/near/210182664">said</a>:</p>
<blockquote>
<p>I think we said that we'd use this meeting to plan our first sprint</p>
</blockquote>
<p>Indeed</p>



<a name="210182791"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182791" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182791">(Sep 15 2020 at 20:04)</a>:</h4>
<p>So, we talked last week about some goals</p>



<a name="210182819"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182819" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182819">(Sep 15 2020 at 20:04)</a>:</h4>
<p>But we mostly dug deep into the shared type library bit</p>



<a name="210182897"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182897" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182897">(Sep 15 2020 at 20:04)</a>:</h4>
<p>So, I can see this being a short(er) meeting</p>



<a name="210182924"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182924" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182924">(Sep 15 2020 at 20:04)</a>:</h4>
<p>even though we didn't talk about rustc integration yet, I think that goal is clearer than the type lib work</p>



<a name="210182996"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210182996" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210182996">(Sep 15 2020 at 20:05)</a>:</h4>
<p>Though the scope might be very large to get full rustc integration</p>



<a name="210183101"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183101" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183101">(Sep 15 2020 at 20:06)</a>:</h4>
<p>like, I tried running some rustc tests, and noticed that auto traits might be quite important there</p>



<a name="210183158"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183158" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183158">(Sep 15 2020 at 20:06)</a>:</h4>
<p>Yeah, on the rustc side, I would say there's a couple things:</p>



<a name="210183177"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183177" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183177">(Sep 15 2020 at 20:06)</a>:</h4>
<p>(are we taking notes in some doc?)</p>



<a name="210183202"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183202" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183202">(Sep 15 2020 at 20:06)</a>:</h4>
<p>1) <code>kind()</code> -&gt; <code>kind(tcx)</code> and/or <code>kind() -&gt; data()</code></p>



<a name="210183210"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183210" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183210">(Sep 15 2020 at 20:06)</a>:</h4>
<p><a href="https://hackmd.io/s1MfBn4bRjyir-aqHZzbKQ">https://hackmd.io/s1MfBn4bRjyir-aqHZzbKQ</a></p>



<a name="210183296"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183296" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183296">(Sep 15 2020 at 20:07)</a>:</h4>
<p>2) Making <code>Binder</code> track bound vars</p>



<a name="210183311"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183311" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183311">(Sep 15 2020 at 20:07)</a>:</h4>
<p>(which is a multiple step process)</p>



<a name="210183335"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183335" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183335">(Sep 15 2020 at 20:07)</a>:</h4>
<p>3) Refactoring away <code>Param</code></p>



<a name="210183470"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183470" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183470">(Sep 15 2020 at 20:08)</a>:</h4>
<p>On the Chalk side, there's also a few things that are pretty important (I've mentioned a few before):</p>



<a name="210183489"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183489" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183489">(Sep 15 2020 at 20:08)</a>:</h4>
<p>1) Subtyping/Variance (being worked on)</p>



<a name="210183499"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183499" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183499">(Sep 15 2020 at 20:09)</a>:</h4>
<p>2) Placeholder canonicalization</p>



<a name="210183525"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183525" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183525">(Sep 15 2020 at 20:09)</a>:</h4>
<p>3) Auto traits (to an extent)</p>



<a name="210183539"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183539" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183539">(Sep 15 2020 at 20:09)</a>:</h4>
<p>4) <code>ReStatic</code> (to an extent)</p>



<a name="210183635"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183635" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183635">(Sep 15 2020 at 20:10)</a>:</h4>
<p>(I also added some of these to the tracking issue, though it's pretty rough and incomplete atm: <a href="https://github.com/rust-lang/wg-traits/issues/25">https://github.com/rust-lang/wg-traits/issues/25</a>)</p>



<a name="210183641"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183641" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183641">(Sep 15 2020 at 20:10)</a>:</h4>
<p>hm, what's restatic?</p>



<a name="210183668"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183668" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183668">(Sep 15 2020 at 20:10)</a>:</h4>
<p>Just having a notion of <code>'static</code> lifetime</p>



<a name="210183707"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183707" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183707">(Sep 15 2020 at 20:10)</a>:</h4>
<p>I can revive my placeholder canonicaliztion branch, but it's somewhat blocked on <a href="https://github.com/rust-lang/chalk/issues/568">#568</a></p>



<a name="210183764"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183764" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183764">(Sep 15 2020 at 20:11)</a>:</h4>
<p>And, another thing I remembered is different but hasn't come up much, is rustc considers bound vars as WF, chalk doesn't</p>



<a name="210183804"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183804" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183804">(Sep 15 2020 at 20:11)</a>:</h4>
<p>that may be a matter of setting up the initial environment correctly more than anything</p>



<a name="210183816"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183816" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183816">(Sep 15 2020 at 20:11)</a>:</h4>
<p><span class="user-mention" data-user-id="251766">@Areredify</span> seems like a discussion we should prioritize</p>



<a name="210183820"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183820" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183820">(Sep 15 2020 at 20:11)</a>:</h4>
<p>I guess I would expect that <code>WellFormed(T)</code> or what have you is "injected" into chalk's environment</p>



<a name="210183924"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210183924" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210183924">(Sep 15 2020 at 20:12)</a>:</h4>
<p>Well</p>



<a name="210184033"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184033" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184033">(Sep 15 2020 at 20:13)</a>:</h4>
<p>It might be that it's a <code>WellFormed(T)</code> that's getting changed to a <code>WellFormed(!0)</code> because of the param substitution</p>



<a name="210184070"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184070" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184070">(Sep 15 2020 at 20:13)</a>:</h4>
<p>But IIRC, I think we actually get goals a like <code>WellFormed(^0.0)</code></p>



<a name="210184132"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184132" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184132">(Sep 15 2020 at 20:14)</a>:</h4>
<p><a href="https://github.com/rust-lang/rust/blob/a874956d940ecb3ed524b6176a171219ac4787ea/compiler/rustc_traits/src/chalk/lowering.rs#L169">https://github.com/rust-lang/rust/blob/a874956d940ecb3ed524b6176a171219ac4787ea/compiler/rustc_traits/src/chalk/lowering.rs#L169</a></p>



<a name="210184186"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184186" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184186">(Sep 15 2020 at 20:14)</a>:</h4>
<p>Oops yeah, it's probably the placeholder "lowering"</p>



<a name="210184188"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184188" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184188">(Sep 15 2020 at 20:14)</a>:</h4>
<p>(<code>!</code> being placeholder, <code>^</code> being bound var)</p>



<a name="210184239"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184239" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184239">(Sep 15 2020 at 20:14)</a>:</h4>
<p>I just wrote up a quick <a href="https://gist.github.com/nikomatsakis/cd8cf828c15621c654edd2ede6d24e1b">MVP proposal</a> for <code>kind -&gt; data</code></p>



<a name="210184259"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184259" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184259">(Sep 15 2020 at 20:14)</a>:</h4>
<p>I had hoped to do that <em>before</em> this meeting but... :)</p>



<a name="210184263"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184263" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184263">(Sep 15 2020 at 20:14)</a>:</h4>
<p>anything missing from that ?</p>



<a name="210184281"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184281" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184281">(Sep 15 2020 at 20:15)</a>:</h4>
<p><span class="user-mention" data-user-id="255061">@LeSeulArtichaut</span> still wants to take that on, right?</p>



<a name="210184290"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184290" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184290">(Sep 15 2020 at 20:15)</a>:</h4>
<p>right</p>



<a name="210184300"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184300" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184300">(Sep 15 2020 at 20:15)</a>:</h4>
<p>one thought is that maybe I should extend the MCP to cover add'l things</p>



<a name="210184307"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184307" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184307">(Sep 15 2020 at 20:15)</a>:</h4>
<p>like region -&gt; lifetime or whatever</p>



<a name="210184322"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184322" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184322">(Sep 15 2020 at 20:15)</a>:</h4>
<p>but I guess it seems better to me to focus on one question at a time</p>



<a name="210184374"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184374" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184374">(Sep 15 2020 at 20:15)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> LGTM</p>



<a name="210184383"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184383" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184383">(Sep 15 2020 at 20:15)</a>:</h4>
<p>Right, maybe even prefer two smaller proposals at the same time instead of one larger one</p>



<a name="210184428"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184428" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184428">(Sep 15 2020 at 20:16)</a>:</h4>
<p>yes, that</p>



<a name="210184441"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184441" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184441">(Sep 15 2020 at 20:16)</a>:</h4>
<p>otherwise the discussion gets confusing</p>



<a name="210184450"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184450" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184450">(Sep 15 2020 at 20:16)</a>:</h4>
<p>I definitely prefer multiple smaller proposals</p>



<a name="210184454"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184454" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184454">(Sep 15 2020 at 20:16)</a>:</h4>
<p>we had "format the world", now it's time for "rename the world"</p>



<a name="210184493"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184493" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184493">(Sep 15 2020 at 20:16)</a>:</h4>
<p>filed <a href="https://github.com/rust-lang/compiler-team/issues/359">https://github.com/rust-lang/compiler-team/issues/359</a></p>



<a name="210184546"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184546" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184546">(Sep 15 2020 at 20:17)</a>:</h4>
<p>Particularly people might prefer region instead of lifetime, and I would rather not add additional overhead of bikeshedding</p>



<a name="210184610"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184610" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184610">(Sep 15 2020 at 20:17)</a>:</h4>
<p>I think in that particular case I was somewhat leaning towards renaming things in chalk</p>



<a name="210184634"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184634" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184634">(Sep 15 2020 at 20:18)</a>:</h4>
<p>there are still some changes needed on rustc side though (introducing the <code>data</code> method, in particular)</p>



<a name="210184721"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184721" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184721">(Sep 15 2020 at 20:18)</a>:</h4>
<p>I don't have a strong opinion about the name though, I guess lifetime might be more familiar to new contributors</p>



<a name="210184731"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184731" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184731">(Sep 15 2020 at 20:18)</a>:</h4>
<p>anyway let's leave that for now</p>



<a name="210184827"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184827" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184827">(Sep 15 2020 at 20:19)</a>:</h4>
<p>Right, so</p>



<a name="210184867"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184867" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184867">(Sep 15 2020 at 20:19)</a>:</h4>
<p>I'm really hesitant to start adding a bunch of goals to the sprint doc</p>



<a name="210184880"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184880" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184880">(Sep 15 2020 at 20:19)</a>:</h4>
<p>Since, I don't really want to add things that aren't going to be finished</p>



<a name="210184889"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184889" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184889">(Sep 15 2020 at 20:19)</a>:</h4>
<p>right</p>



<a name="210184974"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184974" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184974">(Sep 15 2020 at 20:20)</a>:</h4>
<p>one thing I had hoped to do before this meeting was to break out the shared type library stuff into issues; but I don't think we need to spend more meeting time on it, we have a fairly granular breakdown there</p>



<a name="210184994"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210184994" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210184994">(Sep 15 2020 at 20:20)</a>:</h4>
<p>I would be interested maybe to touch base a bit more on some of those rustc integration blockers you mentioned</p>



<a name="210185100"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185100" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185100">(Sep 15 2020 at 20:21)</a>:</h4>
<p>Sounds good to me</p>



<a name="210185120"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185120" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185120">(Sep 15 2020 at 20:21)</a>:</h4>
<p>Chalk side or rustc side to start?</p>



<a name="210185276"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185276" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185276">(Sep 15 2020 at 20:23)</a>:</h4>
<p>erm, okay, let's start Chalk side then?</p>



<a name="210185306"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185306" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185306">(Sep 15 2020 at 20:23)</a>:</h4>
<p>sure</p>



<a name="210185324"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185324" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185324">(Sep 15 2020 at 20:23)</a>:</h4>
<p>well one specific thing I was confused about waas the mention of auto traits</p>



<a name="210185345"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185345" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185345">(Sep 15 2020 at 20:23)</a>:</h4>
<p>what is missing there again? auto traits for builtin types?</p>



<a name="210185349"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185349" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185349">(Sep 15 2020 at 20:23)</a>:</h4>
<p>yes</p>



<a name="210185358"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185358" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185358">(Sep 15 2020 at 20:23)</a>:</h4>
<p>that seems like a good sprint goal</p>



<a name="210185378"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185378" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185378">(Sep 15 2020 at 20:23)</a>:</h4>
<p>Probably</p>



<a name="210185397"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185397" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185397">(Sep 15 2020 at 20:24)</a>:</h4>
<p>Yeah, running some random rustc tests with <code>-Zchalk</code> ran into "the trait <code>Send</code> is not implemented for <code>&amp;str</code>"</p>



<a name="210185473"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185473" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185473">(Sep 15 2020 at 20:24)</a>:</h4>
<p>Ah interesting! I hadn't seen that</p>



<a name="210185491"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185491" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185491">(Sep 15 2020 at 20:24)</a>:</h4>
<p>As an example, but I imagine it would be pretty important to get more tests green</p>



<a name="210185496"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185496" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185496">(Sep 15 2020 at 20:24)</a>:</h4>
<p>Seems like pretty easy low hanging fruit</p>



<a name="210185512"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185512" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185512">(Sep 15 2020 at 20:24)</a>:</h4>
<p>Someone was working on it, right?</p>



<a name="210185556"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185556" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185556">(Sep 15 2020 at 20:25)</a>:</h4>
<p>Also we got one more builtin trait to care for</p>



<a name="210185575"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185575" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185575">(Sep 15 2020 at 20:25)</a>:</h4>
<p><code>DiscriminantKind</code></p>



<a name="210185604"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185604" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185604">(Sep 15 2020 at 20:25)</a>:</h4>
<p>Oh, uh maybe. I think so. Let me double check</p>



<a name="210185673"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185673" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185673">(Sep 15 2020 at 20:26)</a>:</h4>
<p>ah yeah, <span class="user-mention" data-user-id="335294">@memoryleak47</span></p>



<a name="210185744"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185744" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185744">(Sep 15 2020 at 20:26)</a>:</h4>
<p>probably should ping and assign them if they still want to on github</p>



<a name="210185774"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185774" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185774">(Sep 15 2020 at 20:26)</a>:</h4>
<p>Good idea</p>



<a name="210185786"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185786" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185786">(Sep 15 2020 at 20:27)</a>:</h4>
<p><code>DiscriminantKind</code> .. fun</p>



<a name="210185861"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185861" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185861">(Sep 15 2020 at 20:27)</a>:</h4>
<p>but that seems relatively low priority</p>



<a name="210185880"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185880" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185880">(Sep 15 2020 at 20:27)</a>:</h4>
<p>although we may wind up needing it for some things in core or something</p>



<a name="210185899"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210185899" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210185899">(Sep 15 2020 at 20:27)</a>:</h4>
<p>yeah, and it's not hard, since we already want type repr data for other builtin traits</p>



<a name="210186007"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186007" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186007">(Sep 15 2020 at 20:28)</a>:</h4>
<p>/me goes to check what <code>DiscriminantKind</code> is...</p>



<a name="210186045"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186045" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186045">(Sep 15 2020 at 20:29)</a>:</h4>
<p>it's basically</p>
<div class="codehilite"><pre><span></span><code>if (T is enum) {
   T repr
} else {
   u8
}
</code></pre></div>



<a name="210186085"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186085" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186085">(Sep 15 2020 at 20:29)</a>:</h4>
<p>and something something generator repr</p>



<a name="210186134"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186134" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186134">(Sep 15 2020 at 20:29)</a>:</h4>
<p>we kinda wandered off though</p>



<a name="210186189"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186189" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186189">(Sep 15 2020 at 20:30)</a>:</h4>
<p>Why do we need to add it?</p>



<a name="210186213"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186213" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186213">(Sep 15 2020 at 20:30)</a>:</h4>
<p><span class="user-mention" data-user-id="232957">@Jack Huey</span> it's used for the <code>std::mem::discriminant</code> API</p>



<a name="210186228"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186228" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186228">(Sep 15 2020 at 20:30)</a>:</h4>
<p>which returns a <code>Discriminant&lt;T&gt;</code></p>



<a name="210186233"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186233" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186233">(Sep 15 2020 at 20:30)</a>:</h4>
<p>where <code>T</code> is the type of some enum</p>



<a name="210186246"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186246" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186246">(Sep 15 2020 at 20:30)</a>:</h4>
<p>(or really any type)</p>



<a name="210186272"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186272" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186272">(Sep 15 2020 at 20:30)</a>:</h4>
<p><span class="user-mention" data-user-id="232957">@Jack Huey</span> because all impls of it are builtin</p>



<a name="210186284"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186284" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186284">(Sep 15 2020 at 20:30)</a>:</h4>
<p>you have <code>struct Discriminant&lt;T&gt; { value: &lt;T as DiscriminantKind&gt;::Type }</code> or something</p>



<a name="210186288"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186288" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186288">(Sep 15 2020 at 20:30)</a>:</h4>
<p>oh</p>



<a name="210186291"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186291" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186291">(Sep 15 2020 at 20:30)</a>:</h4>
<p>okay</p>



<a name="210186311"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186311" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186311">(Sep 15 2020 at 20:31)</a>:</h4>
<p>it's kind of an internal impl detail</p>



<a name="210186321"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186321" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186321">(Sep 15 2020 at 20:31)</a>:</h4>
<p>We can add it to the list, but let's try to get back on topic</p>



<a name="210186336"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186336" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186336">(Sep 15 2020 at 20:31)</a>:</h4>
<p>yeah, I <em>think</em> it's only needed for folks that use that API</p>



<a name="210186347"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186347" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186347">(Sep 15 2020 at 20:31)</a>:</h4>
<p>which is why I said low priority</p>



<a name="210186364"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186364" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186364">(Sep 15 2020 at 20:31)</a>:</h4>
<p>the next thing that seems like a relatively easy thing to pick off is <code>ReStatic</code></p>



<a name="210186385"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186385" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186385">(Sep 15 2020 at 20:31)</a>:</h4>
<p>Yeah, super easy</p>



<a name="210186431"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186431" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186431">(Sep 15 2020 at 20:32)</a>:</h4>
<p>I think for now we should probalby just add it to chalk</p>



<a name="210186432"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186432" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186432">(Sep 15 2020 at 20:32)</a>:</h4>
<p>Some of the work can be stolen from <a href="https://github.com/rust-lang/chalk/compare/master...nikomatsakis:outlives">https://github.com/rust-lang/chalk/compare/master...nikomatsakis:outlives</a></p>



<a name="210186511"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186511" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186511">(Sep 15 2020 at 20:32)</a>:</h4>
<p>Nice, always good to have some good-first-issue tasks</p>



<a name="210186513"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186513" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186513">(Sep 15 2020 at 20:32)</a>:</h4>
<p>in the future we could avoid it <em>potentially</em>, but <code>'static</code> really <em>is</em> special, so I'm not sure if that's necessary</p>



<a name="210186534"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186534" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186534">(Sep 15 2020 at 20:32)</a>:</h4>
<p>(it's "top" in the lattice, or "bottom", depending on your POV...)</p>



<a name="210186566"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186566" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186566">(Sep 15 2020 at 20:32)</a>:</h4>
<p>I thought I made an issue for that, whoops</p>



<a name="210186636"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186636" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186636">(Sep 15 2020 at 20:33)</a>:</h4>
<p>I will do that after the meeting</p>



<a name="210186662"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186662" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186662">(Sep 15 2020 at 20:33)</a>:</h4>
<p>Next blocking item:</p>



<a name="210186688"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186688" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186688">(Sep 15 2020 at 20:33)</a>:</h4>
<p>Placeholder canonicalization</p>



<a name="210186808"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186808" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186808">(Sep 15 2020 at 20:34)</a>:</h4>
<p>So, this is blocked on <a href="https://github.com/rust-lang-nursery/chalk/issues/568">chalk#568</a>?</p>



<a name="210186836"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186836" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186836">(Sep 15 2020 at 20:34)</a>:</h4>
<p><span class="user-mention" data-user-id="251766">@Areredify</span> I don't remember, did your branch build/pass?</p>



<a name="210186843"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186843" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186843">(Sep 15 2020 at 20:34)</a>:</h4>
<p>no</p>



<a name="210186855"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186855" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186855">(Sep 15 2020 at 20:35)</a>:</h4>
<p><span class="user-mention silent" data-user-id="232957">Jack Huey</span> <a href="#narrow/stream/144729-wg-traits/topic/meeting.202020-09-15/near/210186808">said</a>:</p>
<blockquote>
<p>So, this is blocked on <a href="https://github.com/rust-lang-nursery/chalk/issues/568">chalk#568</a>?</p>
</blockquote>
<p>that surprises me a bit :)</p>



<a name="210186860"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186860" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186860">(Sep 15 2020 at 20:35)</a>:</h4>
<p>it compiled</p>



<a name="210186861"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186861" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186861">(Sep 15 2020 at 20:35)</a>:</h4>
<p>but we could talk about this issue a bit</p>



<a name="210186873"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186873" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186873">(Sep 15 2020 at 20:35)</a>:</h4>
<p>it's not blocked per se</p>



<a name="210186985"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210186985" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210186985">(Sep 15 2020 at 20:36)</a>:</h4>
<p>I still, uh, am not quite sure what the benefits of canonicalizing placeholders are</p>



<a name="210187005"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187005" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187005">(Sep 15 2020 at 20:36)</a>:</h4>
<p>well, it is just <em>more</em> canonical, to start</p>



<a name="210187008"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187008" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187008">(Sep 15 2020 at 20:36)</a>:</h4>
<p>but when we inject clauses into the environment we need to know which bound vars are inference vars and which are placeholder vars</p>



<a name="210187030"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187030" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187030">(Sep 15 2020 at 20:36)</a>:</h4>
<p>it's on the list of possible meeting topics, maybe we should have a design meeting for it?</p>



<a name="210187041"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187041" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187041">(Sep 15 2020 at 20:36)</a>:</h4>
<p>to be able to output <code>Ambigious</code> where needed</p>



<a name="210187053"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187053" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187053">(Sep 15 2020 at 20:36)</a>:</h4>
<p>I see, so they interact</p>



<a name="210187102"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187102" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187102">(Sep 15 2020 at 20:37)</a>:</h4>
<p><span class="user-mention" data-user-id="125131">@detrumi</span> yes, I added it to the list</p>



<a name="210187104"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187104" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187104">(Sep 15 2020 at 20:37)</a>:</h4>
<p>we could certainly schedule to dig into the canonicalization question next meeting</p>



<a name="210187110"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187110" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187110">(Sep 15 2020 at 20:37)</a>:</h4>
<p>I figured we probably don't have time to dig in today</p>



<a name="210187148"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187148" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187148">(Sep 15 2020 at 20:37)</a>:</h4>
<p>(I remember <span class="user-mention" data-user-id="251766">@Areredify</span> and I also had a conversation about it in some topic, so that might be good for someone (maybe <em>cough</em> me) to review before the meeting to prepare a summary)</p>



<a name="210187229"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187229" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187229">(Sep 15 2020 at 20:38)</a>:</h4>
<p>works for me</p>



<a name="210187242"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187242" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187242">(Sep 15 2020 at 20:38)</a>:</h4>
<p>let's put this off until the design meeting then</p>



<a name="210187252"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187252" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187252">(Sep 15 2020 at 20:38)</a>:</h4>
<p>shall I take a "todo item" to do some prep for that?</p>



<a name="210187254"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187254" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187254">(Sep 15 2020 at 20:38)</a>:</h4>
<p>sure</p>



<a name="210187271"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187271" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187271">(Sep 15 2020 at 20:38)</a>:</h4>
<p>Is there anything else placeholder canonicalization is blocked on?</p>



<a name="210187313"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187313" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187313">(Sep 15 2020 at 20:39)</a>:</h4>
<p>I don't think I encountered any other problems</p>



<a name="210187356"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187356" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187356">(Sep 15 2020 at 20:39)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> yes, and I'll add it to action items</p>



<a name="210187458"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187458" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187458">(Sep 15 2020 at 20:40)</a>:</h4>
<p>Ok, rustc blocking items</p>



<a name="210187513"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187513" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187513">(Sep 15 2020 at 20:40)</a>:</h4>
<p>we talked about <code>kind()</code> -&gt; <code>data()</code></p>



<a name="210187536"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187536" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187536">(Sep 15 2020 at 20:40)</a>:</h4>
<p>We discussed <code>Binder</code> refactoring last week a bit</p>



<a name="210187552"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187552" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187552">(Sep 15 2020 at 20:41)</a>:</h4>
<p><code>Param</code> refactoring/removal</p>



<a name="210187558"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187558" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187558">(Sep 15 2020 at 20:41)</a>:</h4>
<p>Um, so</p>



<a name="210187580"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187580" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187580">(Sep 15 2020 at 20:41)</a>:</h4>
<p>I know <span class="user-mention" data-user-id="116009">@nikomatsakis</span> and I discussed this at one point a bit</p>



<a name="210187585"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187585" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187585">(Sep 15 2020 at 20:41)</a>:</h4>
<p>we're getting to some of the harder things</p>



<a name="210187601"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187601" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187601">(Sep 15 2020 at 20:41)</a>:</h4>
<p>Yeah :/</p>



<a name="210187702"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187702" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187702">(Sep 15 2020 at 20:42)</a>:</h4>
<p>my hunch is that this sprint we won't be able to do <em>both</em> "early bound" and "late bound", but we might achieve one of them</p>



<a name="210187743"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187743" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187743">(Sep 15 2020 at 20:42)</a>:</h4>
<p>in terms of <code>Param</code> refactoring, I think it comes down to the fact that rustc has a special type variant representing "early bound" generic types</p>



<a name="210187753"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187753" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187753">(Sep 15 2020 at 20:42)</a>:</h4>
<p>Honestly, the <code>Param</code> work I think needs to be done by someone who has a solid-enough foundation of the rustc codebase</p>



<a name="210187758"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187758" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187758">(Sep 15 2020 at 20:42)</a>:</h4>
<p>e.g., the <code>T</code> in <code>fn foo&lt;T&gt;() { }</code></p>



<a name="210187789"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187789" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187789">(Sep 15 2020 at 20:43)</a>:</h4>
<p>and this is used to mean something "bound" in some contexts (which then gets replaced)</p>



<a name="210187800"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187800" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187800">(Sep 15 2020 at 20:43)</a>:</h4>
<p>and something "free" in most contexts</p>



<a name="210187814"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187814" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187814">(Sep 15 2020 at 20:43)</a>:</h4>
<p>But I do agree <span class="user-mention" data-user-id="116009">@nikomatsakis</span> that we probably can't do both late-bound and early-bound work in this sprint</p>



<a name="210187818"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187818" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187818">(Sep 15 2020 at 20:43)</a>:</h4>
<p>whereas chalk uses bound and placeholder vars consistently</p>



<a name="210187847"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187847" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187847">(Sep 15 2020 at 20:43)</a>:</h4>
<p>I guess, paging it back in, that I did feel like the rustc code would benefit from drawing this distinction</p>



<a name="210187855"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187855" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187855">(Sep 15 2020 at 20:43)</a>:</h4>
<p>I think my <em>fear</em> was that we'd see a perf hit because we'd be doing more substitution</p>



<a name="210187917"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187917" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187917">(Sep 15 2020 at 20:44)</a>:</h4>
<p>and I remember <span class="user-mention" data-user-id="232957">@Jack Huey</span> that I think we had sketched out a <em>bit</em> of how one might start to make this transition?</p>



<a name="210187949"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187949" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187949">(Sep 15 2020 at 20:44)</a>:</h4>
<p>Yeah, we did discuss a bit</p>



<a name="210187954"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187954" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187954">(Sep 15 2020 at 20:44)</a>:</h4>
<p>but if I recall it wasn't all that easy</p>



<a name="210187968"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187968" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187968">(Sep 15 2020 at 20:44)</a>:</h4>
<p>I don't remember if we ever made a real plan</p>



<a name="210187991"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210187991" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210187991">(Sep 15 2020 at 20:44)</a>:</h4>
<p>We kind of agreed it's better to start with late-bound</p>



<a name="210188012"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188012" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188012">(Sep 15 2020 at 20:44)</a>:</h4>
<p>yeah I think my hunch is that it's the kind of refactoring I would do by kind of doing the switch and seeing what breaks, and trying to factor out the fixes into standalone commits</p>



<a name="210188032"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188032" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188032">(Sep 15 2020 at 20:45)</a>:</h4>
<p>I'm curious how we could surface out the performance question as quickly as possible</p>



<a name="210188045"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188045" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188045">(Sep 15 2020 at 20:45)</a>:</h4>
<p>at the moment I'm not sure how to do that beyond trying it</p>



<a name="210188055"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188055" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188055">(Sep 15 2020 at 20:45)</a>:</h4>
<p>True</p>



<a name="210188075"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188075" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188075">(Sep 15 2020 at 20:45)</a>:</h4>
<p>I think we shouldn't spend to much time or thought on it</p>



<a name="210188082"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188082" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188082">(Sep 15 2020 at 20:45)</a>:</h4>
<p>And just leave it at:</p>



<a name="210188098"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188098" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188098">(Sep 15 2020 at 20:45)</a>:</h4>
<p>probably it's not for this sprint, though I might enjoy trying my hand at it, or helping someone else through it</p>



<a name="210188159"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188159" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188159">(Sep 15 2020 at 20:46)</a>:</h4>
<p>If someone <em>experienced</em> with the rustc codebase wants to tackle it, then we can discuss further an make a plan. Otherwise, we need to leave it for now.</p>



<a name="210188171"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188171" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188171">(Sep 15 2020 at 20:46)</a>:</h4>
<p>I would love to see you take a stab at it <span class="user-mention" data-user-id="116009">@nikomatsakis</span></p>



<a name="210188183"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188183" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188183">(Sep 15 2020 at 20:46)</a>:</h4>
<p>You would honestly be the best person to try</p>



<a name="210188207"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188207" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188207">(Sep 15 2020 at 20:46)</a>:</h4>
<p>maybe <span class="user-mention silent" data-user-id="119009">eddyb</span></p>



<a name="210188243"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188243" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188243">(Sep 15 2020 at 20:47)</a>:</h4>
<p>Anyways, let's move on</p>



<a name="210188263"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188263" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188263">(Sep 15 2020 at 20:47)</a>:</h4>
<p>That's all the rustc integration blocking work</p>



<a name="210188272"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188272" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188272">(Sep 15 2020 at 20:47)</a>:</h4>
<p>At least, nothing else comes to mind right now</p>



<a name="210188283"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188283" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188283">(Sep 15 2020 at 20:47)</a>:</h4>
<p>I guess the question is whether there are immediate steps for late-bound? but maybe we've got enough work lined up for now and we can revisit it we run out</p>



<a name="210188295"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188295" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188295">(Sep 15 2020 at 20:47)</a>:</h4>
<p>there aren't <em>that</em> many folks clamoring for issues to pick up</p>



<a name="210188303"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188303" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188303">(Sep 15 2020 at 20:47)</a>:</h4>
<p>I have a WIP branch for late-bound I think</p>



<a name="210188369"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188369" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188369">(Sep 15 2020 at 20:48)</a>:</h4>
<p>that's another case where I think the target is a bit unclear</p>



<a name="210188381"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188381" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188381">(Sep 15 2020 at 20:48)</a>:</h4>
<p><a href="https://github.com/jackh726/rust/tree/binder-refactor">https://github.com/jackh726/rust/tree/binder-refactor</a></p>



<a name="210188475"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188475" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188475">(Sep 15 2020 at 20:49)</a>:</h4>
<p>I started by just seeing if I could just <em>count</em> the bound vars</p>



<a name="210188499"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188499" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188499">(Sep 15 2020 at 20:49)</a>:</h4>
<p>And see what kind of perf effects it had</p>



<a name="210188544"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188544" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188544">(Sep 15 2020 at 20:49)</a>:</h4>
<p>ah interesting</p>



<a name="210188621"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188621" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188621">(Sep 15 2020 at 20:50)</a>:</h4>
<p>there is also strictly more data to intern</p>



<a name="210188637"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188637" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188637">(Sep 15 2020 at 20:50)</a>:</h4>
<p>i.e., in chalk, we intern a list of generic-arg-kinds per binder</p>



<a name="210188653"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188653" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188653">(Sep 15 2020 at 20:50)</a>:</h4>
<p>whereas rustc just recomputes that info on demand</p>



<a name="210188682"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188682" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188682">(Sep 15 2020 at 20:50)</a>:</h4>
<p>right</p>



<a name="210188695"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188695" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188695">(Sep 15 2020 at 20:50)</a>:</h4>
<p>quick question, do we expect chalk to improve rustc performance in the long run, once it's been fully integrated?</p>



<a name="210188738"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188738" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188738">(Sep 15 2020 at 20:51)</a>:</h4>
<p>well I think that's a good idea to measure that way</p>



<a name="210188755"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188755" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188755">(Sep 15 2020 at 20:51)</a>:</h4>
<p>I always had hoped the answer to that to be "yes"</p>



<a name="210188764"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188764" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188764">(Sep 15 2020 at 20:51)</a>:</h4>
<p>I expect so, because of increased caching</p>



<a name="210188778"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188778" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188778">(Sep 15 2020 at 20:51)</a>:</h4>
<p>as well as the opportunity to optimize the solver independently from the rest of rust</p>



<a name="210188810"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188810" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188810">(Sep 15 2020 at 20:51)</a>:</h4>
<p>as well as some other details of how rustc works</p>



<a name="210188817"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188817" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188817">(Sep 15 2020 at 20:51)</a>:</h4>
<p>that I believe make it do similar work many times</p>



<a name="210188836"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188836" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188836">(Sep 15 2020 at 20:51)</a>:</h4>
<p>however, some of those gains can be realized within rustc itself (most notably more caching), and we've done some of that</p>



<a name="210188903"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188903" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188903">(Sep 15 2020 at 20:52)</a>:</h4>
<p>so it may turn out be less than i'd have hoped</p>



<a name="210188911"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188911" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188911">(Sep 15 2020 at 20:52)</a>:</h4>
<p>right, but we can frame the performance losses as an investment for future performance wins</p>



<a name="210188958"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188958" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188958">(Sep 15 2020 at 20:52)</a>:</h4>
<p>Plus, a good deal of work has already gone into rustc to make it fast(er)</p>



<a name="210188983"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210188983" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210188983">(Sep 15 2020 at 20:53)</a>:</h4>
<p>Whereas for Chalk, we've done like no perf optimizations</p>



<a name="210189012"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189012" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189012">(Sep 15 2020 at 20:53)</a>:</h4>
<p>to start out chalk will be slower, yeah, but I was mainly wondering about long-term</p>



<a name="210189052"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189052" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189052">(Sep 15 2020 at 20:53)</a>:</h4>
<p>Anyways, let's for the last few minutes take about design meetings</p>



<a name="210189061"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189061" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189061">(Sep 15 2020 at 20:54)</a>:</h4>
<p>"slowing the compiler some more in 2021" blogpost to announce chalk integration</p>



<a name="210189113"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189113" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189113">(Sep 15 2020 at 20:54)</a>:</h4>
<p>So, I came up with a few meetings to think about this sprint</p>



<a name="210189191"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189191" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189191">(Sep 15 2020 at 20:54)</a>:</h4>
<ul>
<li>Placeholder canonicalization</li>
<li>Removing <code>Param</code> in rustc</li>
<li>Const evaluation</li>
<li>Canonical vs. instantiated program clauses</li>
</ul>



<a name="210189204"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189204" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189204">(Sep 15 2020 at 20:54)</a>:</h4>
<p>The first and fourth seem to be related</p>



<a name="210189227"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189227" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189227">(Sep 15 2020 at 20:55)</a>:</h4>
<p>Or at least, seem like they can be discussed together</p>



<a name="210189354"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189354" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189354">(Sep 15 2020 at 20:56)</a>:</h4>
<p>oh I really want to discuss what do we consider well formed</p>



<a name="210189395"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189395" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189395">(Sep 15 2020 at 20:56)</a>:</h4>
<p>it does feel like we hit questions about that and I don't have a crisp idea what our strategy is</p>



<a name="210189401"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189401" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189401">(Sep 15 2020 at 20:56)</a>:</h4>
<p>it keeps coming up and we never resolve it</p>



<a name="210189426"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189426" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189426">(Sep 15 2020 at 20:56)</a>:</h4>
<p>Example of a question?</p>



<a name="210189497"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189497" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189497">(Sep 15 2020 at 20:57)</a>:</h4>
<p><a href="#narrow/stream/144729-wg-traits/topic/dyn.20X.20.2B.20'a.20isn't.20well-formed/near/209903718">link</a></p>



<a name="210189587"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189587" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189587">(Sep 15 2020 at 20:58)</a>:</h4>
<p>Ah interesting</p>



<a name="210189611"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189611" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189611">(Sep 15 2020 at 20:58)</a>:</h4>
<p>Okay, yeah, I guess good design meeting topic</p>



<a name="210189620"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189620" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189620">(Sep 15 2020 at 20:58)</a>:</h4>
<p>Do we just want to schedule one meeting at a time?</p>



<a name="210189682"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189682" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189682">(Sep 15 2020 at 20:58)</a>:</h4>
<p>(unless there are people that want to attend any one particular discussion but are limited to specific dates)</p>



<a name="210189819"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189819" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189819">(Sep 15 2020 at 20:59)</a>:</h4>
<p>So placeholder canonicalization next week?</p>



<a name="210189820"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189820" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189820">(Sep 15 2020 at 20:59)</a>:</h4>
<p>Okay, so next week we will discussion canonical vs intantiated vars in clauses and placeholder canonicalization</p>



<a name="210189933"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189933" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189933">(Sep 15 2020 at 21:00)</a>:</h4>
<p>I have to run but thanks all; I'll prep a bit for meeting and also work on creating issues</p>



<a name="210189934"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189934" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189934">(Sep 15 2020 at 21:00)</a>:</h4>
<p>Okay, 5:00 now</p>



<a name="210189946"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/meeting%202020-09-15/near/210189946" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/meeting.202020-09-15.html#210189946">(Sep 15 2020 at 21:00)</a>:</h4>
<p>Thanks everyone for coming</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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